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Influences of low-Ti substitution for La and Mg on the electrochemical and kinetic characteristics of AB_3-type hydrogen storage alloy electrodes

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Science china(Technological sciences) 2010年第1期53卷 242-247页

作者： DONG ZhenWei1,2,WU YaoMing1,MA LiQun2,SHEN XiaoDong2 & WANG LiMin1 1 State Key Laboratory of Rare earth Resource Utilization,changchun Institute of Applied Chemistry,Chinese Academy of sciences,C hangchun 130022,china 2 college of Material Science and Engineering,Nanjing university of Technology,Nanjing 210009,china State Key Laboratory of Rare earth Resource Utilization Changchun Institute of Applied Chemistry Chinese Academy of Sciences Changchun China college of Material Science and Engineering Nanjing University of Technology Nanjing China

The(La0.67Mg0.33)1-xTixNi2.75Co0.25(x = 0,0.05,0.10,0.15 and 0.20,at%) alloys were synthesized by arc melting and subsequent heat solid-liquid diffusing *** structure,electrochemical properties and kinetic characteristics of the alloys were investigated *** results showed that all the alloys mainly consisted of the(La,Mg)Ni3,LaNi5 phases,and the lattice parameters and the cell volumes of the(La,Mg)Ni3 and LaNi5 phases decreased with increasing Ti *** alloy electrodes could be activated to reach their maximum discharge capacity within five *** cycle life after 100 charge/discharge cycles(C100/Cmax) and the high-rate dischargeability at a discharge current density of 1200 mA/g first increased and then *** the results showed that low-Ti content in AB3-type hydrogen storage alloys was beneficial to improvements of the overall electrochemical properties,and the optimum overall electrochemical performance of the alloy electrodes was obtained when x = 0.05.

关键词： AB3-type alloy metal hydride electrode microstructure electrochemical property kinetic characteristic

Coexistence of two sympatric and morphologically similar bat species Rhinolophus a nis and Rhinolophus pearsoni

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Progress in Natural Science:Materials International 2008年第5期18卷 523-532页

作者： Tinglei Jiang, Jiang Feng , Keping Sun, Jing Wang college of Urban and Environmental sciences, Northeast Normal university, changchun 130024, china college of Urban and Environmental sciences Northeast Normal University Changchun 130024 China

Ecologists have long focused on the coexistence of sympatric species. Here, we investigated two horseshoe bat species, Rhinolophus a nis and Rhinolophus pearsoni inhabited in the same cave, for their foraging strategies, niche di erentiation, prey selection, and their coexistence status. These two species of horseshoe bats were di erent in the dominant frequency of their echolocation calls, but similar in their morphology. We found evidence for prey selectivity although there was a high degree of overlap in prey categories and sizes. R. a nis and R. pearsoni foraged on 16 and 7 categories insects, respectively, with Pyralidae, Geometridae, Melolonthidae dominating their diets. The degree of trophic niche overlap was 0.69. Pairwise comparisons suggested that there was no obvious di erentiation in prey categories and size. However, high prey availability in the environment (Simpson diversity index = 0.79 and Margalef richness index = 4.12) contributed to their coexistence by dampening the interspeci c competition. Since there are one or more mechanisms facil- itating species coexistence in a community, our results suggest that the spatial niche di erentiation in foraging microhabitats and in for- aging habitats at landscape scale may promote the coexistence of the two bat species. However, additional eld data are needed to con rm this speculation.

关键词： Bats Species coexistence Foraging strategies Niche di erentiation Prey richness

A two-dimensional study on natural convection and heat transfer in the enclosure with heat transfer and radiation coupled in natural convection

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Science china(Technological sciences) 2010年第4期53卷 991-999页

作者： ZHAN NaiYan1,2,YANG Mo1 & XU PeiWei2 1 college of Power Engineering,university of Shanghai for Science and Technology,Shanghiai 200093,china 2 Department of Environmental Engineering,jilin Architectural and Civil Engineering Institute,changchun 130021,china college of Power Engineering University of Shanghai for Science and Technology Shanghiai China Department of Environmental Engineering Jilin Architectural and Civil Engineering Institute Changchun China

Numerical investigation using SIMPLE algorithm with QUICK scheme for natural convection and heat transfer in the enclosure bounded by a solid wall and with heat transfer and radiation coupled in natural convection has been *** various parameters are:Rayleigh number(from 103 to 105),dimensionless conductivity of bounding wall(from 0 to 100),dimensionless wall thickness(from 0 to 0.6) and radiation emissivity of all surfaces(from 0 to 1).The results suggest that flow and heat transfer are influenced by *** is a dominant action on flow and heat *** increase of the thermal conductivity of wall,flow and heat transfer turn *** temperature distribution changes *** the thermal conductivity of wall is over a certain critical number,the increasing trend of flow and heat transfer may *** increase of enclosure wall thickness,flow and heat transfer turn *** the enclosure wall thickness is over a certain critical number,the flow and heat transfer will turn slow.

关键词： conduction natural convection radiation couple numerical simulation

Constraints of authigenic carbonates on trace elements (Sr,Mg) of lacustrine ostracod shells in paleoenviron-ment reconstruction and its mechanism

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Science china earth sciences 2008年第5期51卷 654-664页

作者： HU Guang1,2, JIN ZhangDong1 & ZHANG Fei3 1 State Key Laboratory of Loess and Quaternary Geology, Institute of earth Environment, Chinese Academy of sciences, Xi’an 710075, china 2 Graduate university of the Chinese Academy of sciences, Beijing 100049, china 3 college of Resources and Environmental Science, Nanjing Agricultural university, Nanjing 210095, china State Key Laboratory of Loess and Quaternary Geology Institute of Earth Environment Chinese Academy of Sciences Xi’an China Graduate university of the Chinese Academy of sciences Beijing China college of Resources and Environmental Science Nanjing Agricultural University Nanjing China

Molar ratios of Mg/Ca and Sr/Ca were measured in two species of ostracod shells preserved in the upper core (15–55 m) of the Hequing Basin in Yunnan Province, southwest china. By correlating the molar ratios between Mg/Ca and Sr/Ca and comparing them with Sr concentrations of the sediments, we suggested that: (1) the molar Mg/Ca and Sr/Ca ratio variations in respective ostracod primo reflected the changes in its ambient water composition and ecology; (2) the molar Sr/Ca ratios responded better to the salinity change linearly than Mg/Ca without aragonite precipitation in the system, and otherwise there was no linear relation between them; and (3) the molar Sr/Ca ratios were mainly controlled by salinity and authigenic carbonate precipitation, whereas the molar Mg/Ca ratios were related to both salinity and temperature. In fact, the rate of ostracod growth owing to temperature controls the fluctuation of Mg/Ca in shells. Here, more attentions should be paid to the constraint of authigenic mineral precipitation processes on the trace elements in ostracod shells and to the correlation between these trace elements in biogenic carbonates and compositions of the sediments in systems and in future in vitro experiments.

关键词： ostracod shell molar Sr/Ca ratio molar Mg/Ca ratio environmental response Heqing Basin

Discovery of a pterodactylid pterosaur from the Yixian Formation of western Liaoning,china

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Chinese Science Bulletin 2001年第13期46卷 1112-1117页

作者： WANG Xiaolin & LU Junchang1. Institute of Vertebrate Paleontology and Paleoanthropology, Chinese Academy of sciences, Beijing 100044, china 2. college of earth sciences and Resources, china university of Geo-sciences, Beijing 100083, china 3. Department of Geological sciences, Southern Methodist university, Dallas, TX 75275, USA Institute of Vertebrate Paleontology Chinese Academy of Sciences Beijing 100044 China

A well-preserved pterosaur with nearly complete skull is described from the Lower Cretaceous Yixian Formation at Sihetun in western Liaoning. It is characterized by a low and long crestless skull, slender and pointed teeth, long metacarpal, nearly equal length of metatarsals I -III and short pedal digit V. It is referred to a new genus and species of the family Pterodactylidae: Haopterus gracilis gen. et sp. nov. This is the first pterosaur with a nearly complete skull from the Jehol Biota; it also represents the first non-controversial fossil record of Pterodactylidae in Asia. Haopterus is more derived than Pterodactylus from the Late Jurassic Solnhofen in Germany. This discovery extends the distribution of the family Pterodactylidae from Europe and Africa to Asia and its latest occurrence from the Late Jurassic to the Early Cretaceous. The discovery of Haopterus gracilis provides further evidence for the study of the originand radiation of the Jehol Biota; it also sheds new light on the evolution and

关键词： western Liaoning Early Cretaceous Yixian Formation Pterodactylidae.

Taurine Inhibits Myocardial Fibrosis via PKC-ERK1/2 Signaling Pathways

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Chemical Research in Chinese Universities 2012年第1期28卷 84-90页

作者： WANG Li-ying1,2, LI Hong1 and YANG Shi-jie1 1. Department of Pharmacology, Norman Bethune college of Medicine, jilin university, changchun 130021, P. R. china 2. Department of Physiology, Basic Medicine college, Beihua university, jilin 132013, P. R. china Department of Pharmacology Norman Bethune College of Medicine Jilin University Changchun 130021

Previous studies have demonstrated the important role of taurine in inhibiting proliferation of myofibrob lasts（myoFb） and myocardial fibrosis. However, the underlying mechanisms are unclear. The present study was de signed to shed light on this issue through exploring the signal pathways via in vitro experiments. Angiotension II （AngII） treatment significantly increased myoFb proliferation and the levels of collagens I and III（P〈0.05）, whereas taurine, PKCα（PKC： protein kinase C） specific inhibitor L-threo-dihydro-sphingosine（D4681）, ERK1/2 inhibitor （PD98095） abrogated myoFb proliferation and collagen levels（P〈0.05, P〈0.01, respectively）, and increased the G0/G1 phase rate and decreased S phase rate. Immunocytochemistry, confocal fluorescence staining and image analy sis showed that taurine could inhibit the translocation and expression of p-PKCαin membrane, and then inhibit nuc lear translocation and expression of p-ERK1/2. These results have statistically significant differences compared with those of AngII group（P〈0.01）. Western blot results also show that taurine could inhibit the protein expression of p-PKCα and p-ERK1/2. We used p-PKCα specific inhibitor D4681 in order to elucidate the relationship between p-PKCα and p-ERK1/2 in signal transduction pathways. Finally, the results show that the protein expression of p-ERK1/2 and nuclear translocation were suppressed in D4681 group.

关键词： Taurine Myocardial fibrosis Proliferation Signal transduction Cardiac remodeling

Effect of strontium substitution on the activity of La_(2-x)Sr_xNiO_4(x=0.0-1.2)in NO decomposition

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Science china Chemistry 2007年第1期50卷 41-46页

作者： ZHU JunJiang 1 ,YANG XiangGuang 2 ,XU XueLian 3 &WEI KeMei 1 1 National Research Center of Chemical Fertilizer Catalysts,Fuzhou university,Fuzhou 350002,china 2 changchun Institute of Applied Chemistry,Chinese Academy of sciences,changchun 130022,china 3college of Chemistry&Chemical Engineering,Fuzhou university,Fuzhou 350002,china National Research Center of Chemical Fertilizer Catalysts Fuzhou University Fuzhou China changchun Institute of Applied Chemistry Chinese Academy of Sciences Changchun China college of Chemistry & Chemical Engineering Fuzhou University Fuzhou China

The aim of this work is to study the effect of Sr substitution on the redox properties and catalytic ac- tivity of La2-xSrxNiO4(x=0.0-1.2)for NO *** suggest that the x=0.6 sample shows the highest *** characterization(TPD,TPR,etc.)of samples indicates that the x=0.6 sample possesses suitable abilities in both oxidation and reduction,which facilitates the proceeding of oxygen desorption and NO *** temperature below 700℃,the oxygen desorption is difficult, and is the rate-determining step of NO *** the increase of reaction temperature(T> 700℃),the oxygen desorption is favorable and,the active adsorption of NO on the active site(NO+Vo+ Ni2+→NO^--Ni3+)turns out to be the rate-determining *** existence of oxygen vacancy is the prerequisite condition for NO decomposition,but its quantity does not relate much to the activity.

关键词： NO decomposition La2-xSrxNiO4 TPD TPR oxygen vacancy

Measurement of the linear electro-optic coefficient of a minute cBN sample

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Science china(Technological sciences) 2005年第2期48卷 233-340页

作者： DOU Qingping1, , MA Haitao1, JIA Gang1, CHEN Zhanguo1 2 & ZHANG Tiechen3 1. college of Electronic Science and Engineering, State Key Laboratory on Integrated Optoelectronics, jilin university, changchun 130023, china 2. Mudanjiang Normal Institute, Mudanjiang 157012, china 3. State Key Laboratory of Superhard Materials, jilin university, changchun 130012, china college of Electronic Science and Engineering State Key Laboratory on Integrated Optoelectronics Jilin University Changchun China Mudanjiang Normal Institute Mudanjiang China State Key Laboratory of Superhard Materials Jilin University Changchun China

Cubic boron nitride (cBN) is a kind of artificial (synthetic) crystal. Transverse electro-optic modulation in a minute cBN sample was carried out. Basing on the practical form of the crystal, we established the theoretical and experimental method according to the sample. For the first time, the linear electro-optic effect was observed in cBN, and half-wave voltage of the cBN sample was measured successfully. Furthermore, its linear electro-optic coefficient was calculated at 1.17×10?14 m/V.

关键词： cBN crystal, linear electro-optic effect, half-wave voltage, linear electro-optic coefficient.

Genomics,metagenomics,and microbial oceanography—A sea of opportunities

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Science china earth sciences 2011年第4期54卷 473-480页

作者： FANG JiaSong 1,2 &ZHANG Li 3 1 State Key Laboratory of Marine Geology,Tongji university,Shanghai 200092,china 2 college of Natural and Computational sciences,Hawaii Pacific university,Kaneohe,HI 96744,USA 3State Key Laboratory of Geological Processes and Mineral Resources,Faculty of earth sciences,china university of Geosciences,Wuhan 430074,china State Key Laboratory of Marine Geology Tongji University Shanghai China college of Natural and Computational sciences Hawaii Pacific University Kaneohe USA State Key Laboratory of Geological Processes and Mineral Resources Faculty of Earth Sciences China University of Geosciences Wuhan China

Microbial oceanography is an emerging discipline resulted from the interaction,cross-fertilization and integration of life science and ocean *** oceanography integrates the principles of marine microbiology,microbial ecology and oceanography to study the role of microorganisms in the biogeochemical dynamics of natural marine *** application of genomics tools to study marine microbes is resulting in rapid advancements in microbial oceanography that has important implications in global carbon cycle,climate change,and ecosystem *** we review the application of genomics and metagenomics in microbial oceanography and suggest future directions in microbial oceanography research.

关键词： microbial oceanography genomics metagenomics genes biomass bacteria archaea eukarya phylogeny physiology metabolism ecology biogeochemistry microbiology ecosystem function